<style>
    body {
        width: 780px;
        text-align: center
    }
    .box {
        height: 100px;
        width: 300px;
        background: red;
    }
    #top {
        overflow: hidden;
    }
    #bottom {
        border: 1px solid black;
    }
</style>
<body>
    <div id="top">
        <div id="top-left" class="box" style="float: left"></div>
        <div id="top-right" class="box" style="float: right"></div>
    </div>
    <div id="bottom">
        <!-- Due to the overflow property of the top div, this div should be laid beneath the top, rather than inline -->
        <div id="text">foobar</div>
    </div>
</body>
